1. Field of the Invention
The present invention relates to a filtering apparatus of a hard disk drive, and more particularly, to a filtering apparatus of a hard disk drive having an improved structure so that filtering efficiency is improved.
2. Description of the Related Art
Hard disk drives (HDDs), one of the auxiliary memory devices of a computer, read data stored from a magnetic disk and record data on the magnetic disk using a magnetic head.
FIG. 1 is a perspective view illustrating a hard disk drive adopting a conventional filtering apparatus. Referring to FIG. 1, a hard disk drive includes a housing 10, a spindle motor 30 installed inside of the housing 10 to rotate a magnetic disk (a hard disk) 20, an actuator 40 having a magnetic head (not shown) to record data on the disk 20 and to reproduce data from the disk 20, and a filtering apparatus 50 to filter tiny particles existing inside the housing 10.
The housing 10 is installed in a main body of a computer and includes a base plate 11 to support the spindle motor 30 and the actuator 40, and a cover plate 12 coupled to the base plate 11 to protect the disk 20 by encompassing the same.
The actuator 40 is installed on the base plate 11 to pivot around a pivot shaft 47 by a voice coil motor 48. The actuator 40 includes an arm 46 coupled to the pivot shaft 47 to pivot and a suspension 44 installed on the arm 46 to support a slider 42, on which the magnetic head is mounted, to be elastically biased toward a surface of the disk 20.
The disk 20 is a recording medium to record data and one or a plurality of disks can be included in the computer and are separated a predetermined distance from each other and rotatable by a spindle motor 30.
The filtering apparatus 50 filters and removes tiny particles such as dust existing inside the housing 10.
Tiny particles may remain in the hard disk drive which are not completely removed during an assembly process. Also, when the hard disk drive is moved, tiny particles may be generated as the slider 42, where the magnetic head is mounted, collides against a surface of the disk 20 by an external impact, or as the slider 42 produces friction with a surface of a parking zone of the disk 20 when the disk 20 starts to rotate or stops rotating. In the meantime, in a lamp loading method, particles can be generated as a lamp and an actuator produce friction during loading and unloading of the actuator.
The tiny particles existing in the housing 10 of the hard disk drive due to a variety of reasons may contaminate the surface of the disk 20 by adhering thereto. Also, the magnetic head and the surface of the disk 20 may be damaged as tiny particles on the surface of the disk 20 collides against the magnetic head during the rotation of the disk 20. Accordingly, data recording and reproduction performance or reliability of the magnetic head may be deteriorated.
Therefore, there is a need to remove tiny particles, which cause physical damage to the magnetic head and the surface of the disk 20 and which have bad effects on the performance of the magnetic head, from the surface of the disk 20.
The filter apparatus 50 includes a recirculation filter 52 and holders 54 and 56 included on the cover plate 12 to support the filter 52. A groove 58 into which a lower end portion of the filter 52 is inserted is formed in the base plate 11.
FIGS. 2 through 4 show a conventional filtering apparatus having the above structure. FIG. 2 is a plan view of part of the cover plate where the filtering apparatus shown in FIG. 1 is installed FIG. 3 is a magnified plan view of a portion A of FIG. 2, showing the flow of air passing through the filter. FIG. 4 is a perspective view showing the recirculation filter used in the conventional filtering apparatus.
Referring to FIGS. 2 and 3, two holders 54 and 56 facing each other to support both ends of the filter 52 are included on the cover plate 12. The holder 54 protrudes from the bottom surface of the cover plate 12 and the holder 56 is integrally formed with a side wall of the cover plate 12. Support grooves 54a and 56a into which the both ends of the filter 52 are inserted are formed in the holders 54 and 56, respectively.
When the disk 20 is rotated in a direction R, the air in the housing 10 flows in the same direction. Some of the flowing air passes through the filter 52 and tiny particles such as dust included in the flowing air are filtered and removed by the filter 52.
However, as shown in FIG. 4, the filter 52 includes a filtering portion 52a having a structure such as a sponge through which the air can pass to filter particles and an edge portion 52b having a thickness thinner than that of the filtering portion 52a and encompassing the edge of the filtering portion 52a. Thus, as shown in FIG. 3, when the filter 52 having the above shape is inserted into the support grooves 54a and 56a of the holders 54 and 56, a gap is present between the support grooves 54a and 56a and the filter 52. Also, each side end portion of the filtering portion 52a is disposed in the support grooves 54a and 56a. Accordingly, since the filtering portion 52a directly contacts the side walls of the support grooves 54a and 56a, a sealing performance is deteriorated.
Due to the above structure, in the conventional filtering apparatus 50, some of the air flowing toward the filter 52 escapes through the gap between the filter 52 and the support grooves 54a and 56a, thus an efficiency in collecting tiny particles in the flowing air is deteriorated. Of the air flowing toward the filter 52, the flow of air adjacent to the support grooves 54a and 56a is curved toward both end portions of the filtering portion 52a disposed in the support grooves 54a and 56a. Accordingly, the smooth flow of air around the support grooves 54a and 56a is prevented so that resistance to the flow of air passing through the filter 52 increases. As a result, the amount of air flowing toward the filter 52 is reduced so that an efficiency in filtering the flowing air inside the hard disk drive is lowered.